March 6, 2014 (Chinavestor) Share price of E Commerce China Dangdang (NASDAQ:DANG) surged from a sleepy $10 range to $18.55 in just two weeks. Reason for the unusual advance is fundamental. E Commerce China Dangdang (NASDAQ:DANG) returned to profitability and beat analys extpectations both on top and the bottom line. Plus it upped previous guidance going into 2014. Here is the key going forward: price is what you pay but value is what you get. And when a stock price runs up too much, too fast- like SouFun Holdings (NYSE:SFUN) and Tesla Motors (NASDAQ:TSLA) did, investors have to think how to trade the stock.